反应详情

A solution of 6-amino-4H-benzo[1,4]oxazin-3-one (commercial; 6.49 g, 39.5 mmol) and tert-butyl-dimethyl-[(R)-2-oxiranyl-ethoxy]-silane (first eluting compound in step H.i; 8.0 g, 39.5 mmol) in EtOH/H2O (9:1; 240 mL) was heated at 80° C. for 2 days. The mixture was concentrated under reduced pressure. Residual starting aniline could be removed by addition of Et2O/MeOH followed by filtration. The filtrate containing the product was concentrated under reduced pressure and the residue was purified by CC (DCM/MeOH/NH4OH 1000:50:4) to afford the title intermediate as a brown oil (5.82 g, 40% yield).

1. concentrationThe mixture was concentrated under reduced pressure
2. customcould be removed by addition of Et2O/MeOH
3. filtrationfollowed by filtration
4. additionThe filtrate containing the product
5. concentrationwas concentrated under reduced pressure
6. customthe residue was purified by CC (DCM/MeOH/NH4OH 1000:50:4)